This invention generally relates to apparatus and methods for excavating and transplanting trees. The invention relates more specifically to equipment which utilizes curved ground piercing blades moveably supported on a ring assembly positioned around a tree to be transplanted, the blades being forced and guided down into the ground to completely encompass a tree root ball which can thereafter be lifted out of the ground and transported for subsequent transplantation. In addition, this invention relates to equipment for inclining the tree at an angle to permit transporting large trees down public roadways having overhead obstacles, such as electrical lines and overpasses.
Land developers are becoming more interested in trying to save trees on the land they are developing. In fact, some communities, such as Austin, Tex., have an ordinance protecting trees 19 inches in diameter or larger. Since such trees are usually in the way of the planned construction, they must be moved to another location on the site or elsewhere. For the trees to have a reasonable chance of surviving, a substantial root ball must be moved with the tree.
Previous tree moving equipment, such as the DeHaan device, U.S. Pat. No. 4,226,033, the Lemond device, U.S. Pat. No. 4,286,398, the Newman device, and U.S. Pat. No. 4,301,605, the Stocker device, employed a plurality of blades that severed the root ball from the ground and formed a supporting structure for the root ball and tree as it was lifted out of the ground and moved to its new location. The blades were guided into the ground by various types of guide members that engaged the blade over a substantial portion of their length. This resulted in significant structure high above the ground. This structure is a disadvantage to utilizing the prior art equipment, such that trees with low limbs frequently required the limbs to be removed in order to be transplanted.
The Korenek tree transplanter, U.S. Pat. No. 4,658,518, attempted to alleviate this problem, but it also has its disadvantages. Use of the Korenek equipment can be limited when utilized on terrain that is not level because the mast requires the ring assembly, tree and root ball to be raised vertically. The problem may become evident when the apparatus is utilized on terrain having more than minimal slope, such as that exceeding 10 degrees. Many applications require the transplantation of a tree either from or to a terrain that has a significant slope, such that the blades of the previous equipment might not be properly aligned with the axis of the tree, thereby resulting in excavating a root ball insufficient to protect the tree and ensure successful transplantation. Since the ring structure and blades are set in a given plane in relation to the terrain, the Korenek equipment may not allow the excavation of a tree and adequate root ball from severely sloped terrain, such as the side of a mountain. Further problems may arise with the Korenek equipment when the tree to be excavated and has a crooked trunk or significant branches which the mast would interfere with, such that in positioning the transplanting apparatus around the tree, the trunk may force the misalignment of the ring structure and blades in relation to the root ball, resulting in the excavation of an inadequate or asymmetrical root ball, and thereby sacrificing the health of the tree and decreasing the likelihood of successful transplantation.
The Korenek apparatus includes a mast on which a ring structure vertically raises and lowers in relation to the ground. The mast stands in a strictly vertical plane and may interfere with the limbs of large trees, possibly injuring the tree limbs or requiring the removal of several tree limbs in order to accurately position the apparatus around the tree. Further, this problem makes such devices particularly disadvantageous for use in nurseries where it is desirable to plant and cultivate trees as closely as possible to utilize the available land most efficiently. Because of the space required for maneuvering and positioning conventional devices to remove such trees, the trees must be planted a greater distance apart than would generally be desirable from the standpoint of utilizing available space in the most efficient manner possible.
Additionally, those skilled in the art have learned that the mast arrangement is often not strong or rigid enough to use the apparatus with large trees, such that additional braces have been attached between the mast and various points on the ring structure. These additional supports may also interfere with the limbs of the tree to be excavated, resulting in the need to again remove several limbs prior to excavation. To desirably position the ring assembly of the Korenek device for a tree excavating operation, the lower end of the mast is closely adjacent the ground surface. This close spacing e.g., approximately 8 inches, presents ground clearance problems when using the equipment, particularly in muddy environments.
Moreover, once a tree is excavated with the Korenek equipment, the weight of the excavated tree bears substantially upon the mast. To counteract the moment about the mast created by the excessive weight of the tree, a particular prime mover must be selected to prevent the mast from breaking and to prevent the excavated tree from falling backwards to the ground. This limitation in selecting a prime mover of appropriate weight to prevent such malfunction is particularly disfavored to those skilled in the art, since many applications have limitations in the availability of prime movers of various weights.
The Korenek apparatus is also susceptible to malfunctions attributed to wear and fracture of the blade guides which guide the blades into the ground. The guides in the Korenek apparatus receive excessive loading from the blades, a problem intensified by the minimal contact area between the blades and the guides. This loading creates excessive wear on the guides, resulting in the failure of the guides or blades, and thereby driving up maintenance requirements of the apparatus, decreasing the reliability of the device, and ultimately increasing operating costs of the device. The guides also provide no effective means for removing debris that becomes lodged between the guides and the blades during use, a factor that leads to further malfunction or fracture of the apparatus. Also, as the Korenek transplanting apparatus is repeatedly used and the force of the blades on the guides and debris accumulates between the guides and the blades, significant wear is effected on the guides, such that the engagement of the guides and the blades is lessened, thereby preventing the blades from being accurately driven into the ground. This also results in the inadequate excavation of the root ball and diminishes the likelihood of tree survival.
Finally, utilization of the Korenek tree transplanter can be a tedious process, requiring multiple bolting and unbolting of the ring sections to and from one another. Since tree excavating apparatus are often utilized in the construction and nursery industries where time is of the essence, a tedious procedure is not cost effective. Utilizing this equipment requires the additional utilization of multiple tools and several people, thereby increasing both the complexity, execution time and cost of excavating a single tree.
Prior art tree excavators have used hydraulic cylinders each secured to a blade and to a fixed member, such as an annular ring member or a blade guide. Blades are individually inserted into the ground from forces provided by these cylinders. In many prior art tree excavation equipment, the cylinders are rather lengthy, such that the blade may be moved from a fully retracted position to a completed excavation stroke with a full stroke of the linear motor. Thereby, the linear cylinders are rather lengthy and extend upward from the fixed member, creating further height limitations problems, frequently necessitating removal of low hanging branches and limbs from the tree. U.S. application Ser. No. 09/477,513 discloses a tree excavator providing relatively shorter hydraulic cylinders, and includes a series of holes along an outer, longitudinal length of each blade for sequentially connecting, disconnecting and reconnecting the cylinder as the blade is inserted into the ground. A pin and clevis arrangement is disclosed for removably securing the cylinder to the blade. However, such apparatus requires significant time and manual labor to connect, disconnect, and reconnect each cylinder on each blade, both when the blades are inserted to excavate the tree, and when the blades are subsequently moved in the opposite direction to replant the excavated tree.
When excavating and transporting relatively tall trees, clearance under obstructions along the transportation route, such as overhead power lines and roadway overpasses, can be problematic. With some prior art tree transplanting equipment, an excavated tree may be tilted as an angle with respect to the ground, in a direction toward the truck or prime mover. Thereby, the maximum permitted angle of inclination for the tree is limited by interference of the tree trunk, limbs, or branches with the prime mover.
An additional problem with tilting prior art tree moving equipment is encountered when transporting the tree over large distances or at higher speeds, such as on highways. The prior art equipment tilts the tree forward, toward the truck or prime mover and in the direction of transport. The forward inclination of the tree unfavorably positions the branches with respect to wind and obstacles encountered by the tree. Thereby, encountered obstacles and/or high wind tend to bend the branches backward, toward the base of the tree, which may result in hanging the branches and limbs on the obstacle and/or breaking the limbs or branches. At roadway speeds, the wind loading on a tree angled forward into the wind may also create sizeable stress and forces on the tree as the limbs are bent downward. Limbs, branches, and/or foliage thereby may be relatively easily broken or damaged.
Another problem with transporting relatively tall trees at an inclination over roadways using prior art equipment is decreased verticle clearance under obstacles, such as porta-cocheres or electrical lines, due to the base of the tree being carried or positioned above a vehicle axle and/or wheels. Thereby, trees exhibiting large diameter root balls and/or large diameter upper portions may incur relatively low clearance obstacles during transportation, which may necessitate removing branches or the obstacle.
In U.S. Pat. No. 4,403,427, Dahlquist discloses a truck mounted tree planter which transports a tree inclined forward, positioning the branch and limb portion of the tree toward and over the truck cab. In addition, the root ball is supported above the truck rear frame and axles, limiting verticle clearance. U.S. Pat. No. 5,081,941 to Weeks discloses a loader mounted apparatus for excavating and transplanting trees. The Weeks transporter is limited in its ability to transport large trees in highly inclined positions, and is not well suited for long-distance or roadway transportation.
In U.S. Pat. No. 5,485,691, Stevens discloses a tree excavating and transporting apparatus which also imposes height limitations and clearance problems for large trees, in that the root ball is positioned above the transporter""s axle. In addition, the tree is inclined forward, in the direction of travel and toward the prime mover. Thereby, potential transportation problems are imposed, including branches being broken due to wind and engagement with obstructions, and engagement of taller trees with the prime mover, imposing potential height clearance problems.
U.S. Pat. No. 4,341,025 to Stocker also discloses a truck mounted tree transporter, which inclines the tree forward over the cab of the truck, imposing minimum clearance problems for large diameter trees and relatively low hanging obstructions. The previously discussed problems of forward inclining the tree are also inherent with this apparatus.
It is highly desirable to provide a tree excavating and transplanting apparatus that can transplant relatively large trees down roadways with reduced damage to the tree. It is also highly desirable to transport relatively large trees under relatively low height clearance obstructions, such as power lines, porta-cocheres, and bridges. It is desirable to tilt a tree rearward at up to 90 degrees while transporting the tree, relative to the vertical trunk position, to minimize wind and obstruction damage to the tree.
A preferred machine for excavating and transplanting large trees involves a tilting annular ring assembly pivotally supported in an supporting frame. The tilting annular ring assembly may support a plurality of blades moveably supported thereon. The annular ring assembly and the supporting frame are positioned around a tree by a prime mover. The blades sever a root ball from the ground and form a supporting structure for the root ball and tree as it is lifted out of the ground, tilted rearward with respect to the prime mover, and moved to a new location. Typically, the annular ring assembly includes a front rigid section and one or more rear gate sections pivotally attached to the rigid section, such that the gate sections can be rotated open to allow the machine to be positioned around the tree.
The present invention provides a machine and method for excavating and transplanting large trees, and affords solutions to some of the challenges of excavating and transporting trees experienced in the prior art. This invention offers advantages over the prior art in that it may improve excavation of trees from and transplantation of trees to uneven or sloped terrain, while maintaining the tree in a gravitationally plumb posture. This machine permits tilting a front or rear portion of the support frame with respect to the other, while additionally permitting tilting of the blade-supporting annular ring assembly with respect to the supporting frame. Thereby, the present invention permits additional machine flexibility and positioning options for operations on uneven or sloped terrain.
A primary object of this invention is to provide a tree mover that can tilt relatively large trees rearward with respect to a prime mover at the front of the machine. Thereby, the tree may be transported under relatively low-clearance overhead obstructions, and may additionally minimize wind and obstruction damage to limbs and branches, compared to prior art machines. The invention may also substantially improve the tree excavating and transplanting process, such as by eliminating the need for removing overhead obstacles, or permitting access to transplanting areas which may previously have been inaccessible due to such obstacles. Tilting the tree rearward, away from the prime mover, permits tilting a relatively tall tree at angles of up to 90 degrees, without interference or engagement with the prime mover, as experienced with prior art tree movers. Branches tilted rearward may be less prone to breaking due to the wind and obstacles encountered during transport, as compared to trees tilted forward, toward the wind and obstacles.
Another primary object of this invention is to provide an excavating machine that offers the ability to excavate, transport, and transplant large trees, including relatively tall trees, and to further improve such excavating and transplanting operations on uneven or sloping terrain. The preferred embodiment disclosed affords this characteristic through the arrangement of four hydraulic elevating cylinders engaged with the support frame and three moveable base supports. Two elevating cylinders are each pivotally attached at one end to the support frame which pivotally supports the blade carrying annular ring assembly, and are each attached at the other end to one of the two moveable rear base supports. Two front elevating cylinders may be pivotally attached at one end to the support frame and at another end to an over-center neck mechanism, which in turn may be pivotally attached at one end to the support frame and at an opposing end to a front moveable base support. The three moveable base supports may be supported upon one or more axles, tires, wheels, and/or tracks, to make the moveable supports rollable supports, such that a prime mover may move the tree mover apparatus.
The two rear hydraulic elevating cylinders are each attached at an opposing end to a respective moveable base. By extending the elevating cylinder pistons to different lengths to best position the ring assembly around the tree, the ring assembly may maintain a substantially level position with respect to the terrain. However, due to the dimensional distances between the moveable base supports, on highly uneven terrain, additional vertical positioning of the blades is desirable. Such improved positioning is achieved through this invention by pivotally supporting the annular ring assembly within the support frame. Thereby, the blades and annular ring assembly may be further aligned with respect to the terrain and tree trunk position by pivoting the annular ring with respect to the support frame. The likelihood of tree survival may be increased since pivoting the annular ring with respect to the support frame may permit excavation of a more accurately excavated root ball than previously possible with the prior art.
This invention may also utilize a plurality of relatively shorter length blade movers/hydraulic cylinders to better position the tree mover around tree trunks having relatively low hanging limbs and branches. With tree movers utilizing long-stroke hydraulic cylinders, such limbs and branches frequently require removal in order to position the tree mover around the tree trunk. However, use of prior art short stroke hydraulic cylinders is relatively time consuming and labor intensive to reposition each cylinder in order to make subsequent steps or stokes for blade movement.
It is a feature of this invention to reduce the time required excavating and transplanting a tree using a tree mover apparatus utilizing a plurality of the shorter, relatively low-clearance hydraulic cylinders. An improved keel assembly and method of operating the cylinders is provided by the present invention, reducing the labor and time required to reposition each of the hydraulic cylinders between stokes.
In a preferred embodiment, a keel is provided on each blade along an inside surface of the circumference formed by the plurality of ground piercing blades. Each keel may be provided with a plurality of keel slot profiles, each designed for laterally engaging a lower end of a hydraulic cylinder. An upper end of each blade moving hydraulic cylinder may be pivotally positioned relative to the lower end such that the cylinder may be pivoted slightly along a pendulum-like arc into engagement with or from engagement with a selected keel profile. These features are favorable over the prior art in that workers may efficiently operate the tree mover apparatus in a timely fashion, eliminating time consuming hydraulic cylinder removal and reattachment to each keel, following each cylinder stoke of the relatively short hydraulic cylinder. These features are also advantageous over the prior art in that they may decrease the number of additional tools necessary to repeatedly attach the blade movers to the ground piercing blades.
The forgoing disclosure and description of the machine for excavating and transplanting large trees and components is illustrative and explanatory thereof. This invention is not intended to be limited to the illustrated and discussed embodiments, as one skilled in the art will appreciate that various changes in the size, shape and materials, as well as in the details of the construction and combinations of features of the tree excavating, transporting and transplanting machine may be made without departing from the spirit of the invention.